Update (08. March 2012): Wiley has informed me that they just fixed the issue.
70 GB of digital content from Wiley’s Major Reference Works can be downloaded for free from Wiley’s web server. This is probably not intended, as Wiley still charges hundreds or even thousand of Euros for each one. I notified them of this fact several times during the last two months. They do not seem to mind. In this post I explain how I found out about this, how one can download the content, and why this is probably legal (at least in some jurisdictions).